Sheet-metal belt-conveyer for heat-treating furnaces



SHEET METAL BELT CONVEYER FOR HEAT TREATING FURNACES Filed May 27, 1.931

Patented May 2, 1933 PAT F E Q E RICHARD KAIER, OF CRANFORD, NEVT JERSEY, ASSIGNOR TO THE SINGER MANUFAC- TURING COMPANY, 01? ELIZABETH, NEVI JERSEY, A CORPORATION OF NEW JERSEY SHEET-METAL BELT-CONVEYER FOR HEAT-TREATING- FURNACES Application filed May 27,

This invention relates to a belt for conveying work through a heat-treating furnace and particularly to an endless belt for continuously conveying work-pieces buried in 5 a thin layer of carburizing material through a furnace for the carburization of such workpieces, as disclosed in the U. S. patent to Willard and Kaier, No. 1,792,456, of Feb. 10, 1931.

The invention has for an object to provide a strong, durable and inexpensive conveyerbelt for the work in question which is resistant to distortion and will retain its ability to run freely around the pulleys of the con veyer system without stiffening under the action of the heat and pulverized carburizing material or other conditions to which it is subjected in use.

The invention comprises the devices, combinations and arrangements of parts hereinafter described and claimed.

The features of the invention and the advantages attained thereby will be readily understood by those skilled in the art from the following detailed description of a pre ferred embodiment thereof illustrated in the accompanying drawing in which Fig. l is a top plan View of a sheet-metal belt-conveyor embodying the invention; the sections of the conveyor being in their initially assembled relation to one another. Fig. 2 is a section on the line 2-2, of Fig. 1. Fig. 3 is a top plan view of the conveyer with the sections in the working relation they assume relative to one another after the conveyor has been put to use, and Fig. is a section on the line H, of Fig. 3.

The belt-conveyer illustrated comprises a series of sheet-metal sections 1 disposed in edge-to-edge relation; the adjoining edges of the sections extending widthwise or transversely of the belt. The sections 1 are per forated at 2 along their adjoining edges and wire edge-connectors in the form of coils 3 are threaded through the perforations 2, as

1931. Serial no. 540,335.

shown in Figs. 1 and 2, to connect the sections of the belt together. Embraced within each coil 3 is a reinforcing member or rod l which is thicker than the sheet-metal sections 1 and is preferably welded at 5 to the adjacent edge of one of the sheet-metal sections within the coil 8. The welds 5 need not be continuous widthwise of the belt but may be formed at spaced spots such, for example, as at the ends and center of the rods 4.

To facilitate manufacture of the belt, the coils 3 are preferably initially made of true spiral form so that they may be readily threaded through the perforations 2 by rotation of such coils about their axes; the edge of one sheet-metal section overlapping the reinforcing rod l of the adjoining section. The ends of the coils 3 are preferably anchored at 3 to prevent loosening of such ends. After the belt has been subjected to use in a furnace the lengthwise strain to which the belt is subjected tends to flatten the coils 3 to the oval form shown in Fig. 41-. If it were not for the relatively thick reinforcing rods 4, the flattening or collapse of the coils 3 would continue until they engaged the upper and lower surfaces of sections 1 and thus destroyed the flexibility of the hinge-connections. The relatively thick reinforcing rods l within the coils 3 prevent collapse of such coils beyond the form shown in Fig. 4 and maintain a suitable space be tween the upper and lower convolutions of such coils for a free hinge action of the sheet-metal sections, as indicated in dotted lines at the right-hand end of Figs. 2 and 4'. As belt-conveyors of this type are usually made in endless form and are required to run over pulleys, it is important that the flexibility of the hinge-connections be maintained under the working conditions to which the belt is subjected. Otherwise, premature distortion and failure of the belt will occur due to the stiffening of the hingeconnections.

The present belt is particularly adapted for use in continuous case-hardening furnaces of the type illustrated in said Villard and Kaier patent, wherein the belt-conveyer must carry not only the work-pieces but also a thin layer of pulverized carburizing material in which the work-pieces are buried.

Having thus set forth the nature of the invention, what I claim herein is l. A belt-tension transmitting hinge connection for adjoining sections of a sheetmetal belt-conveyer comprising, a pair of sheet-metal belt-sections perforated along their adjacent edges and arranged initially with their edges overlapping, a true cyli n drical spiral wire coil threaded through the perforations of said overlapping edges, and a reinforcing rod secured to one of said sections, said rod being thicker than said beltsections and disposed within said coil, the diameter of said coil being initally great enough to permit said sections to be pulled apart under the working tension on the belt sufliciently to permit the initially overlapping edges to be drawn into the same plane and out of overlapping relation.

2. A conveyer-belt comprising a plurality of sheet-metal belt-tension-transrnitting sections arranged in edge-to-edge relation, said sections having series of apertures spaced inwardly from their adjoining edges, wire edge-connectors passing through said apertures over and under said adjoining edges, and a reinforcing strip welded to one edge of each section and'adjoining the non-reinforced edge of an adjacent section, said strips being embraced within the respective wire edge-connectors, said wire edge-connectors being initially formed as true cylindrical spirals connecting said adjoining edges in overlapping relation, the diameter of the eylindrical spirals being great enough to permit suficient deformation under the Workiug tension on the belt-sections to draw the overlapping edge-portions into edge-to-edge abutting relation.

3. A belt-tension transmitting hinge-connection for adjoining sections of a sheetmetal belt-conveyer comprising a pair of sheet-metal belt-sections having overlapping edge-portions, said sections having series of perforations adjacent said overlapping edgeportions, and a true cylindrical spiral wire coil threaded through said perforations, the diameter of said coil being initially great enough to permit said sections to be pulled apart under the Working tension on the belt sufliciently to permit the initially overlapping edges to be drawn down into the same plane and out of overlapping relation.

i. A belt-tension transmitting hinge-connection for adjoining sections of a sheetmetal belt-conveyer comprising a pair of sheet-metal belt-sections having overlapping edge-portions, said sections having series of RICHARD KAIER, 

